ACTG 285 - A Pilot Study of Stem Cell Mobilization and Harvesting from the Peripheral Blood Using Filgrastim. The study explored whether the ability of Filgrastim to mobilize CD34+ stem cells into the peripheral blood differs markedly among individuals with various stages of HIV-1 infection and HIV-1 seronegative individuals. The study's objectives were to determine the safety of stem cell harvesting and to determine the surface phenotypic and functional characteristics of both freshly harvested and cryopreserved stem cells that have been mobilized into the peripheral blood subsequent to the administration of Filgrastim in subjects at various stages of HIV-1 infection. Results of this trial have not yet been published.